Circuit Control Apparatus and Method

1. A circuit control apparatus for establishing a connection to a communication partner via a public circuit network or via a computer network, the circuit control apparatus comprising: a specifying information storing part configured to store specifying information for specifying called parties to which the circuit control apparatus originates a call to establish a connection via the public circuit network; a checking part configured to check whether a telephone number of a called party exists in the specifying information storing part; a circuit control part configured to originated said call for establishing a connection to the called party; and a changing part configured to change specifying information in the specifying information storing part, wherein when the checking part determines that the telephone number of the called party exists in the specifying information storing part, the circuit control part originates said call to the called party via the public circuit network in order to connect to the called party, and originates another call to the called party via the computer network in the background in order to determine if a connection to the called party can be established via the computer network, and the circuit control part causes the changing part to delete the telephone number from the specifying information storing part if a connection to the called party can be established via the computer network, and when the checking part determines that the telephone number of the called party does not exist in the specifying information storing part, the circuit control part originates a call via the computer network to the called party, and when the circuit control part determines that the circuit control apparatus cannot connect to the called party via the computer network, the changing part adds the telephone number of the called party to the specifying information storing part, then, the circuit control part originates a call to the called party via the public circuit network.

2. The circuit control apparatus as claimed in claim 1 , wherein the changing part deletes the specific telephone number from the specifying information storing part when a predetermined effective term elapses after the specific telephone number is added to the specifying information storing part.

3. The circuit control apparatus as claimed in claim 1 , wherein the changing part adds a telephone number or a part of a telephone number to the specifying information storing part as the identifying information on the basis of an input from the outside of the circuit control apparatus.

4. The circuit control apparatus as claimed in claim 3 , wherein, when a number of digits of a telephone number of a called party is larger than that of a number registered in the specifying information storing part, the circuit control part compares top digits of the telephone number with the registered number, and the circuit control part originates a call to the telephone number via the public circuit network if the top digits and the registered number are the same.

5. The circuit control apparatus as claimed in claim 1 , wherein, after a connection to a called party is established, the changing part adds a telephone number of the called party to the specifying information storing part or the changing part deletes the telephone number of the called party from the specifying information storing part.

6. The circuit control apparatus as claimed in claim 1 , wherein the changing part edits, according to an input from the outside of the circuit control apparatus, only specifying information that is added to the specifying information storing part.

7. The circuit control apparatus as claimed in claim 1 , the circuit control apparatus further comprising: a use circuit enforcedly determining part configured to cause the circuit control apparatus to try to establish a connection to a called party via the computer network regardless of whether the called party is included in the specifying information storing part when receiving an instruction to use the computer network from outside of the circuit control apparatus.

8. The circuit control apparatus as claimed in claim 1 , wherein, when a call origination interrupt request is received while performing a call origination process to establish a connection to a specific telephone number via the computer network, the circuit control part interrupts the call origination process.

9. The circuit control apparatus as claimed in claim 8 , wherein the changing part adds the specific telephone number into the specifying information storing part.

10. The circuit control apparatus as claimed in claim 1 , wherein, when a call origination interrupt request is received while performing a call origination process to establish a connection to a specific telephone number via the public circuit network, the circuit control part interrupts the call origination process and performs a call origination process via the computer network to the specific telephone number.

11. The circuit control apparatus as claimed in claim 7 , wherein, if the circuit control apparatus successfully establishes the connection to the called party via the computer network, the changing part deletes a telephone number of the called party from the specifying information storing part.

12. The circuit control apparatus as claimed in claim 10 , wherein, if the circuit control apparatus successfully establishes the connection to the specific telephone number via the computer network, the changing part deletes the specific telephone number from the specifying information storing part.

13. The circuit control apparatus as claimed in claim 1 , the circuit control apparatus further comprising: a circuit type display part configured to display a type of a circuit via which the circuit control apparatus is originating a call.

14. The circuit control apparatus as claimed in claim 1 , the circuit control apparatus further comprising: a ringing part configured to output a circuit type specific ringback tone that is assigned to each type of a circuit used for originating a call, wherein, when starting originating a call via an originating circuit, the circuit control part causes the ringing part to output the circuit type specific ringback tone that corresponds to a type of the originating circuit.

15. A circuit control method for use in a circuit control apparatus for establishing a connection to a communication partner via a public circuit network or via a computer network, wherein the circuit control apparatus includes a specifying information storing part for storing specifying information for specifying called parties to which the circuit control apparatus originates a call to establish a connection via the public circuit network, the circuit control method comprising: checking whether a telephone number of a called party exists in the specifying information part; circuit controlling immediately originating said call for establishing a connection to the called party; and changing specifying information in the specifying information storing part, wherein when the checking determines that the determines that the telephone number of the called party exists in the specifying information storing part. the circuit controlling originates said call to the called party via the public circuit network in order to connect to the called party, and originates another call to the called party via the computer network in the background in order to determine if a connection to the called party can be established via the computer network, and the circuit controlling causes the changing to delete the telephone number from the specifying information storing part if a connection to the called party can be established via the computer network, and when the checking determines that the telephone number of the called party does not exist in the specifying information storing part, the circuit controlling originates a call via the computer network to the called party, and when the circuit controlling determines that the circuit control apparatus cannot connect to the called party via the computer network, the changing adds the telephone number of the called party to the specifying information storing part, then, the circuit controlling originates a call to the called party via the public circuit network.

16. The circuit control method as claimed in claim 15 , wherein the specific telephone number is deleted from the specifying information storing part when a predetermined effective term elapses after the specific telephone number is added to the specifying information storing part.

17. The circuit control method as claimed in claim 15 , wherein a telephone number or a part of a telephone number is added to the specifying information storing part as the identifying information on the basis of an input from the outside of the circuit control apparatus.

18. The circuit control method as claimed in claim 17 , wherein, when a number of digits of a telephone number of a called party is larger than that of a number registered in the specifying information storing part, the circuit control apparatus compares top digits of the telephone number with the registered number, and the circuit control apparatus originates a call to the telephone number via the public circuit network if the top digits and the registered number are the same.

19. The circuit control method as claimed in claim 15 , wherein, after a connection to a called party is established, the circuit control apparatus adds a telephone number of the called party to the specifying information storing part or deletes the telephone number of the called party from the specifying information storing part.

20. The circuit control method as claimed in claim 15 , wherein the circuit control apparatus edits, according to an input from the outside of the circuit control apparatus, only specifying information that is added to the specifying information storing part.

21. The circuit control method as claimed in claim 15 , wherein the circuit control apparatus tries to establish a connection to a called party via the computer network regardless of whether the called party is included in the specifying information storing part when the circuit control apparatus receives an instruction to use the computer network for originating a call from outside of the circuit control apparatus.

22. The circuit control method as claimed in claim 15 , wherein, when a call origination interrupt request is received while performing a call origination process to establish a connection to a specific telephone number via the computer network, the circuit control apparatus interrupts the call origination process.

23. The circuit control method as claimed in claim 22 , wherein the circuit control apparatus adds the specific telephone number into the specifying information storing part.

24. The circuit control method as claimed in claim 15 , wherein, when a call origination interrupt request is received while performing a call origination process to establish a connection to a specific telephone number via the public circuit network, the circuit control apparatus interrupts the call origination process and performs a call origination process via the computer network to the specific telephone number.

25. The circuit control method as claimed in claim 21 , wherein, if the circuit control apparatus successfully establishes the connection to the called party via the computer network, the circuit control apparatus deletes a telephone number of the called party from the specifying information storing part.

26. The circuit control method as claimed in claim 24 , wherein, if the circuit control apparatus successfully establishes the connection to the specific telephone number via the computer network, the circuit control apparatus deletes the specific telephone number from the specifying information storing part.

27. The circuit control method as claimed in claim 15 , wherein the circuit control apparatus displays a type of a circuit via which the circuit control apparatus is originating a call.

28. The circuit control method as claimed in claim 15 , wherein, when the circuit control apparatus starts originating a call via an originating circuit, the circuit control apparatus starts outputting a circuit type specific ringback tone that corresponds to a type of the originating circuit.